Search

Background: Sepsis, a systemic inflammatory condition, is a leading cause of mortality due to cardiovascular injury. Sepsis and cellular senescence are closely related, yet the specific mechanisms are still unclear. This study aims to identify a novel therapeutic target for mitigating sepsis-induced myocardial injury., Methods: We initially assessed serum inflammatory markers and myocardial injury indicators in septic mice. This involved observing inflammatory cell infiltration in ventricular muscle tissue, assessing cardiac function, and recording electrocardiograms. We examined the expression of connexin 40 (Cx40) and connexin 43 (Cx43) and analyzed mitochondrial structures in ventricular tissues. A conditional heart-specific Nppb knockout mouse model was then developed in mice to evaluate these changes. Ventricular tissues were analyzed via mRNA sequencing to identify differentially expressed genes (DEGs), which were cross-referenced with senescence-related genes to identify key hub genes. The expression and distribution of hub genes were subsequently analyzed by single-cell analysis. Finally, the expression of the senescence-related gene CCL2, along with cardiac structure and function, was validated in a conditional heart-specific Nppb knockout sepsis mouse model., Results: Myocardial injury severity positively correlated with serum brain natriuretic peptide (BNP) in septic mice. Conditional heart-specific Nppb knockout improved myocardial injury outcomes in mice with sepsis. The DEGs identified in the conditional heart-specific Nppb knockout model overlapped with senescence-related genes, identifying seven upregulated genes associated with inflammation, cardiac contraction and apoptotic pathways. Single-cell analysis confirmed high CCL2 levels and an increased macrophage presence correlating with sepsis progression. Conditional heart-specific Nppb knockout reduced CCL2 levels, which were associated with improved cardiac structure and function., Conclusion: This study confirms that conditional heart-specific Nppb knockout reduces CCL2 expression, thereby ameliorating myocardial injury in septic mice. Targeting Nppb to regulate the senescence-related gene CCL2 may represent an effective strategy for treating myocardial injury in septic patients., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Ischemia/reperfusion (I/R) injury has been demonstrated to exert a significant role in acute myocardial infarction (AMI), which constitutes a crucial cause of AMI. Ferroptosis represents a novel form of cell death that is intimately linked to myocardial ischemia-reperfusion (MIR) injury. Urolithin A (UA), an intestinal metabolite of ellagitannins, has not been fully elucidated for its role in MIR injury. In the present study, we analyzed the effects of UA on ischemia-reperfusion-induced oxidative stress and ferroptosis both in vitro and in vivo, and explored the potential mechanisms of UA action. The results indicated that UA was capable of protecting the heart from ischemia-reperfusion injury and enhancing cardiac function both in vitro and in vivo. In addition, UA also attenuated oxidative stress, mitochondrial damage, and ferroptosis during MIR. Mechanistically, UA not only augmented the Nrf2 expression but also promoted Nrf2 entry into the nucleus and activated the downstream antioxidant defense system. Moreover, after the inhibition of Nrf2, the myocardial protective function of UA was lost, and its function of attenuating oxidative stress and ferroptosis was suppressed. In conclusion, we found that UA protected the heart from ischemia-reperfusion injury by attenuating oxidative stress and ferroptosis through the Nrf2 signaling pathway, suggesting that UA might be a potential therapeutic agent for the treatment of AMI., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cardiac remodeling refers to the abnormal changes in cardiac structure and function caused by various pathological conditions. It is an inevitable pathological process in the occurrence and development of heart failure and is related to a variety of cardiovascular diseases. Inflammation and apoptosis are critical pathological processes involved in cardiac remodeling. Neuregulin 4 (Nrg 4) is an adipokine produced primarily by brown adipose tissue that may play a protective role in a variety of inflammatory diseases. The aim of this study was to investigate whether Nrg4 can delay the progression of cardiac remodeling by regulating AMPK/NF-κB pathway, inhibiting inflammation and apoptosis. In our study, we established a model of cardiac remodeling in mice after 14 days of isoproterenol (ISO) intervention, and then gave Nrg4 treatment for another 4 weeks. The cardiac function, the degree of myocardial hypertrophy and myocardial fibrosis of the mice were observed. At the same time, the levels of apoptosis-related proteins (Bax,Bcl-2,Caspase-3), IL-6,IL-Iβ and TNF-α, as well as the activation level of AMPK/NF-κB signaling pathway were evaluated.Nrg4 alleviated ISO-induced cardiac dysfunction, cardiac hypertrophy and fibrosis in mice. Nrg4 also attenuated ISO-induced apoptosis and reduces levels of inflammatory factors to protect ISO-induced myocardial damage. At the same time, the effect of Nrg4 on AMPK/NF-κB pathway was measured in vivo and in vitro. The administration of an AMPK inhibitor was found to reverse the anti-hypertrophy, anti-inflammatory, and anti-apoptotic effects of Nrg4. Our findings suggest that Nrg4 may play a protective role in cardiac remodeling by inhibiting inflammation and apoptosis via AMPK/NF-κB pathway., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Cardiac lymphatic vessels are important channels for cardiac fluid circulation and immune regulation. In myocardial infarction and chronic heart failure, promoting cardiac lymphangiogenesis is beneficial in reducing cardiac edema and inflammation. However, the specific involvement of cardiac lymphangiogenesis in viral myocarditis (VMC) has not been studied. Despite the recognized participation of macrophages in lymphangiogenesis, the contribution of macrophages to cardiac lymphangiogenesis in VMC is still unclear., Methods: The male Balb/c mice with VMC were grouped according to the time to explore changes in inflammation, cardiac function and lymphangiogenesis. Adeno-associated virus (AAV) was used to determine the effect of cardiac lymphangiogenesis in VMC. Macrophage depletion and VEGF-C C156S treatment were used to investigate the connection between macrophages and cardiac lymphangiogenesis., Results: Cardiac inflammation and lymphatic vessel density were both upregulated, peaking on day 7 following CVB3 infection. After treatment with AAV-sVEGFR3, lymphangiogenesis was inhibited, leading to worsened cardiac dysfunction and aggravated inflammation. However, these effects were reversed by AAV-VEGF-C treatment. Furthermore, macrophages infiltrated the inflamed myocardium and secreted VEGF-C. In vitro, VEGF-C was upregulated when RAW264.7 cells were co-cultured with CVB3. Macrophage depletion in mice with VMC inhibited lymphangiogenesis, while supplementation with VEGF-C C156S depressed it., Conclusion: Collectively, these results indicate that activation of the VEGF-C/VEGFR3 axis exerts a protective effect in CVB3-induced VMC by resolving inflammation and alleviating cardiac dysfunction through increased lymphatic vasculature density, with macrophage-derived VEGF-C partially contributing to this effect., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cardiac fibrosis is associated with myocardial remodeling following myocardial infarction (MI), which can lead to heart failure, arrhythmias, and even death. This study aimed to determine the effects of tubuloside A (TA) on cardiac fibrosis after MI and elucidate their underlying molecular mechanisms. Rats were divided into the following groups: sham (fake surgery), MI, MI + 1 mg/kg TA, and MI + 3 mg/kg TA. Compared with MI, the addition of TA significantly reduced mortality, improved cardiac function, decreased infarct size, and inhibited myocardial injury and fibrosis. To verify the direct targets of TA, we used cellular thermal shift assay and drug affinity responsive target stability to analyze drug-protein interactions and discovered that TA can bind directly to TGM2 and inhibit its enzymatic activity. Furthermore, to investigate whether TA can inhibit the TGF-β1-mediated activation of cardiac fibroblasts (CFs) through TGM2, we overexpressed TGM2 in CF cells and treated them with TA. We found that TA inhibited the activity of TGM2 in CF cells and reduced α-SMA, collagen-I, and collagen-III levels, thereby inhibiting the progression of fibrosis. Similarly, we found that TA could exert anti-inflammatory and antiapoptotic effects by inhibiting TGM2. Overall, we demonstrated that TA is a potential candidate drug for inhibiting the impacts of myocardial infarction and cardiac fibrosis, reducing postinfarction fibrosis by inhibiting the NF-κB signaling pathway and suppressing mitochondrial pathway-mediated apoptosis. Therefore, focusing on drug discovery strategies for TA may provide a promising therapeutic approach for MI., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Previous studies confirmed the regenerative capacity of the mammalian neonatal heart. We recently found that adult heart tissue-derived EVs can protect the heart from myocardial ischemia-reperfusion (I/R). However, the role of EVs from neonatal heart tissue in cardiac healing post-ischemia remains unclear. In the present study, we revealed that intramyocardial administration of neonatal cardiac tissue-derived EVs (ncEVs) alleviated cardiac inflammation, mitigated reperfusion injury, and improved cardiac function in murine I/R models. In vitro, ncEVs inhibited M1 polarization of macrophages induced by LPS while up-regulated their phagocytic function via the miR-133a-3p-Ash1l signaling pathway. Moreover, the administration of ncEVs contributed to cardiac angiogenesis and improved cardiac function in murine myocardial infarction models. Collectively, these results suggested that neonatal heart-derived EVs can regulate the function of macrophages and contribute to cardiac regeneration and function recovery in murine cardiac ischemic models. Therefore, the derivatives in neonatal heart tissue-derived EVs might serve as a potential therapeutic strategy in ischemic diseases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Increased energy intake from carbohydrates has been associated with major cardiovascular outcomes. Mice fed a highly-refined carbohydrate (HC) diet develop cardiac hypertrophy and inflammation. During cardiac injury, NLRP3 inflammasome is activated which results in a local inflammatory response. In this study, we hypothesized that a nom-hypoglycemic dose of glibenclamide may reverses sugar diet-induced cardiac damage by NRLP3 inflammasome inhibition. Mice were fed the HC diet for eight weeks and divided into a group treated with glibenclamide (20 mg/kg, gavage) and another with vehicle for four weeks. Afterward, hearts were excised for morphometric analysis and ex vivo function determination. NLRP3 inflammasome activation was investigated by western blotting and in situ fluorescent detection of reactive oxygen species (ROS) and active caspase-1. The HC diet promotes heart hypertrophy and collagen deposition, which were reverted by glibenclamide without ameliorating HC diet-induced insulin resistance. Changes in cardiac performance were observed in vivo by invasive catheterization and in Langendorff-perfused hearts due to the HC diet, which were prevented by glibenclamide. Hearts from HC diet mice had increased levels of NLRP3 and cleaved IL-1β. Glibenclamide reversed ROS production and caspase-1 activity induced by HC diet. These findings suggest glibenclamide's cardioprotective effects on heart damage caused by the HC diet are related to its inhibitory action on the NLRP3 inflammasome., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Cancer chemotherapy induces cell stress in rapidly dividing cancer cells to trigger their growth arrest and apoptosis. However, adverse effects related to cardiotoxicity underpinned by a limited regenerative potential of the heart limits clinical application: In particular, chemotherapy with doxorubicin (DOXO) causes acute heart injury that can transition to persisting cardiomyopathy (DOXO-CM). Here, we tested if MuRF1 inhibition ("MuRFi") was able to attenuate DOXO-CM. To mimic DOXO chemotherapy, we treated mice over four weeks with five DOXO injections, resulting in a cumulative dosage of 25 mg/kg. At day 28, mice had lower body and heart weights, reduced cardiac cross-sectional myofibrillar areas (CSAs), and disturbed functional ejection fractions (EFs) and fractional shortenings (FS) as indicated by echocardiography (ECHO). In contrast, mice with a 1 g/kg Myomed#205 spiked diet, a previously described experimental MuRFi therapy, showed lower DOXO-CM at day 28, and also reduced acute DOXO cardiac injury at day 7 (single DOXO dose; 15 mg/kg). Underlying molecular signatures using Western blot (WB) assays showed at day 28 reduced phospho-AKT (AKTp) and phospo-4EBP1 (4 EBP1p) levels following DOXO that were normalized following MuRFi treatment. Taken together, our data suggest that MuRFi treatment is suitable to attenuate DOXO-CM by preserving AKTp and 4 EBP1p levels in DOXO stressed cardiomyocytes, thereby supporting de novo protein translation and cardiomyocyte survival under translational arrest stress., Competing Interests: Declaration of competing interest Siegfried Labeit and Volker Adams report a patent filing for MuRFi, and further derivatives for its application to chronic muscle stress states (patent accession No WO2021023643A1). The other authors declare no conflicts of interests., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Pyroptosis has been found to contribute to myocardial ischemia/reperfusion (I/R) injury, but the exact mechanisms that initiate myocardial pyroptosis are not fully elucidated. Sonic hedgehog (SHH) signaling is activated in heart suffered I/R, and intervention of SHH signaling has been demonstrated to protect heart from I/R injury. Caspase recruitment domain-containing protein 10 (CARD10)-B cell lymphoma 10 (BCL10)-mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) (CBM) complex could transduce signals from the membrane and induce inflammatory pathways in non-hematopoietic cells, which could be a downstream effector of SHH signaling pathway. This study aims to explore the role of SHH signaling in I/R-induced myocardial pyroptosis and its relationship with the CBM complex. C57BL/6J mice were subjected to 45 min-ischemia followed by 24 h-reperfusion to establish a myocardial I/R model, and H9c2 cells underwent hypoxia/reoxygenation (H/R) to mimic myocardial I/R model in vitro. Firstly, SHH signaling was significantly activated in heart suffered I/R in an autocrine- or paracrine-dependent manner via its receptor PTCH1, and inhibition of SHH signaling decreased myocardial injury via reducing caspase-11-dependent pyroptosis, concomitant with attenuating CBM complex formation. Secondly, suppression of SHH signaling decreased protein kinase C α (PKCα) level, but inhibition of PKCα attenuated CBM complex formation without impacting the protein levels of SHH and PTCH1. Finally, disruption of the CBM complex prevented MALT1 from recruiting of TRAF6, which was believed to trigger the caspase-11-dependent pyroptosis. Based on these results, we conclude that inhibition of SHH signaling suppresses pyroptosis via attenuating PKCα-mediated CARD10-BCL10-MALT1 complex formation in mouse heart suffered I/R., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Cardiac fibrosis plays a crucial role in the development of heart failure (HF) following myocardial infarction (MI). Endothelial-mesenchymal transition (EndMT) is one of the key drivers of cardiac fibrosis and subsequent cardiac dysfunction. The traditional Chinese medicine formula Bushen Huoxue Yiqi Formula (BHYF) is an effective prescription for treating HF, significantly improving cardiac function in patients. However, the underlying mechanisms of BHYF's efficacy remain inadequately understood., Objective: This study aims to determine whether BHYF ameliorates HF by inhibiting cardiac fibrosis and to elucidate the intrinsic mechanisms involved., Methods: A post-MI HF model was established by ligating the left anterior descending coronary artery in rats, and human umbilical vein endothelial cells (HUVEC) were stimulated with hypoxia/reoxygenation (H/R) in vitro. Active compounds in BHYF were identified using HPLC. Cardiac function and morphology were assessed using echocardiography, TTC staining, HE staining, Masson's trichrome, and Sirius Red staining. The mechanism of action of BHYF was evaluated using Western blotting, immunohistochemistry, and immunofluorescence., Results: A total of 98 compounds, including glycosides, phenolic compounds, carboxylic acids, and others, were identified or preliminarily identified. BHYF improved cardiac function and myocardial damage in rats with MI-induced HF and mitigated cardiac fibrosis by inhibiting EndMT. Mechanistically, BHYF treatment inhibited EndMT by modulating the SIRT1/Notch1 pathway, thereby exerting anti-fibrotic effects in the heart., Conclusion: Targeting EndMT based on the SIRT1/Notch1 pathway, BHYF may represent a novel antifibrotic therapeutic strategy, providing a scientific basis for the development of new cardiovascular drugs., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 The Author(s). Published by Elsevier GmbH.. All rights reserved.)

Objective: The objective of this study was to identify sex differences in ntrahepatocellular (HCL) and intramyocardial lipids (MYCL) and cardiac function in participants with different grades of glucometabolic impairment and different BMI strata., Methods: Data from 503 individuals from 17 clinical experimental studies were analyzed. HCL and MYCL were assessed with 3T and 7T scanners by magnetic resonance spectroscopy. Cardiac function was measured with a 3T scanner using electrocardiogram-gated TrueFISP sequences. Participants were classified as having normoglycemia, prediabetes, or type 2 diabetes. Three-way ANCOVA with post hoc simple effects analyses was used for statistical assessment., Results: Consistent increases of HCL with BMI and deterioration of glucose metabolism, especially in female individuals, were detected. MYCL increased with BMI and glucose impairment in female individuals, but not in male individuals. Sex differences were found in cardiac function loss, with significant effects found among male individuals with worsening glucose metabolism. Myocardial mass and volume of the ventricle were higher in male individuals in all groups. This sex difference narrowed with increasing BMI and with progressing dysglycemia., Conclusions: Sex differences in HCL and MYCL may be associated with a higher cardiovascular disease risk observed in female individuals progressing to diabetes. Further studies are needed to elucidate possible sex differences with advancing glucometabolic impairment and obesity and their potential impact on cardiovascular outcomes., (© 2024 The Author(s). Obesity published by Wiley Periodicals LLC on behalf of The Obesity Society.)

Background: Amphiregulin (AREG) is a growth factor linked to cardioprotection and heart pathology during myocardial stress. Our aim was to investigate cardiac AREG expression, its potential as a postmortem hypothermia marker and its possible stress hormone dependency in different types of deaths., Materials and Methods: Heart RNA was isolated from hypothermic, cardiac and non-cardiac deaths. Relative AREG mRNA levels and urine stress hormone concentrations were measured by qPCR and enzyme-linked immunosorbent assays from eight different death cause groups. Receiver operating characteristic curve was used to evaluate a cut-off point for AREG expression as a hypothermia marker. Regulatory elements were predicted by PROMO., Results: The AREG mRNA levels were significantly higher in hypothermic deaths than in most cardiac and non-cardiac deaths. AREG expression indicated hypothermic deaths with nearly 70% sensitivity and specificity. However, high expression levels were also detected in non-ischaemic deaths. The highest concentrations of adrenaline and cortisol were detected in hypothermic deaths, while the highest noradrenaline concentrations associated with atherosclerotic heart disease (AHD) deaths with acute myocardial infarction and trauma deaths. There were no significant correlations between stress hormones and AREG mRNA in hypothermic and non-cardiac deaths, whereas moderate-to-high associations were detected in cardiac deaths. Putative response elements for cortisol and catecholamines were found in AREG ., Conclusions: Severe hypothermia activates cardiac AREG expression practicable as a postmortem hypothermia marker. Cortisol and catecholamines may act as transcriptional modifiers of this gene, especially in long-term ischaemic heart disease. However, the exact role of these hormones in upregulation of AREG during hypothermia remains unclear.

Cardiovascular diseases (CVDs) are a leading cause of mortality worldwide and are associated with an overactivated sympathetic system. Although exercise training has shown promise in mitigating sympathetic stress-induced cardiac remodeling, the precise mechanisms remain elusive. Here, we demonstrate that exercise significantly upregulates cardiac flavin-containing monooxygenase 2 (FMO2) expression. Notably, we find that exercise training effectively counteracts sympathetic overactivation-induced cardiac dysfunction and fibrosis by enhancing FMO2 expression via adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) activation. Functional investigations employing FMO2 knockdown with adeno-associated virus 9 (AAV9) underscore the necessity for FMO2 expression to protect the heart during exercise in vivo. Furthermore, we identify the krüppel-like factor 4 (KLF4) as a transcriptional mediator of FMO2 that is crucial for the mechanism through which AMPK activation protects against sympathetic overactivation-induced cardiac dysfunction and fibrosis. Taken together, our study reveals a cardioprotective mechanism for exercise training through an AMPK-KLF4-FMO2 signaling pathway that underscores how exercise alleviates cardiac dysfunction induced by excessive sympathetic activation., Competing Interests: Declaration of competing interest None., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Abstract: Wild-type transthyretin amyloid (ATTRwt) deposits in most organs, mainly the heart, ligaments, and tenosynovium. Orthopedic diseases due to ATTRwt deposits often precede overt ATTRwt cardiomyopathy. 99mTc-PYP scintigraphy is highly sensitive in detecting myocardial and extracardiac ATTRwt deposits. However, there are few reports of extracardiac ATTRwt deposits before myocardial deposits confirmed by imaging modalities. We report a case of atrial fibrillation-related heart failure in which 99mTc-PYP scintigraphy showed tracer uptake in extracardiac soft tissues but not in the myocardium, and a biopsy of soft tissues with tracer uptake confirmed ATTRwt deposits. 99mTc-PYP scintigraphy can image extracardiac ATTRwt deposits before myocardial deposits., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Myocardial fibrosis is a critical concern in clinical medicine. This study explores the potential of odoratin as a treatment for myocardial fibrosis and investigates its underlying mechanisms. In vitro experiments involved stimulating primary mouse cardiomyocytes with TGF-β1, followed by odoratin treatment, to assess levels of reactive oxygen species (ROS) and nitric oxide (NO). In vivo, a mouse model of myocardial fibrosis was established using abdominal aortic constriction (AAC) and treated with odoratin. ROS and NO levels in myocardial tissue were then evaluated. Immunofluorescence and Western blotting analysis showed that odoratin reduced excess ROS, enhanced NO production and decreased fibrosis-related protein expression in vitro. In vivo, odoratin significantly improved cardiac function, reduced ROS, increased NO levels and mitigated fibrosis in AAC-induced mice. Both in vitro and in vivo, odoratin inhibited the expression of NADPH oxidase 4 and EZH2, while promoting the expression of phosphorylated endothelial nitric oxide synthase (p-eNOS) and PPARγ. The anti-fibrotic effects of odoratin were reversed by PPARγ antagonism, and EZH2 overexpression diminished PPARγ activation by odoratin. These findings suggest that odoratin may combat myocardial fibrosis by balancing ROS and NO through PPARγ activation, with EZH2 inhibition likely playing a key regulatory role., (© 2024 John Wiley & Sons Australia, Ltd.)

Diabetes mellitus (DM) is characterized by chronic hyperglycemia, and despite intensive glycemic control, the risk of heart failure in patients with diabetes remains high. Diabetes-induced heart failure (DHF) presents a unique metabolic challenge, driven by significant alterations in cardiac substrate metabolism, including increased reliance on fatty acid oxidation, reduced glucose utilization, and impaired mitochondrial function. These metabolic alterations lead to oxidative stress, lipotoxicity, and energy deficits, contributing to the progression of heart failure. Emerging research has identified novel mechanisms involved in the metabolic remodeling of diabetic hearts, such as autophagy dysregulation, epigenetic modifications, polyamine regulation, and branched-chain amino acid (BCAA) metabolism. These processes exacerbate mitochondrial dysfunction and metabolic inflexibility, further impairing cardiac function. Therapeutic interventions targeting these pathways-such as enhancing glucose oxidation, modulating fatty acid metabolism, and optimizing ketone body utilization-show promise in restoring metabolic homeostasis and improving cardiac outcomes. This review explores the key molecular mechanisms driving metabolic remodeling in diabetic hearts, highlights advanced methodologies, and presents the latest therapeutic strategies for mitigating the progression of DHF. Understanding these emerging pathways offers new opportunities to develop targeted therapies that address the root metabolic causes of heart failure in diabetes.

Cardiac fibrosis, characterized by excessive extracellular matrix (ECM) deposition within the myocardium, poses a significant challenge in cardiovascular health, contributing to various cardiac pathologies. Ketone bodies (KBs), particularly β-hydroxybutyrate (β-OHB), have emerged as subjects of interest due to their potential cardioprotective effects. However, their specific influence on cardiac fibrosis remains underexplored. This literature review comprehensively examines the relationship between KBs and cardiac fibrosis, elucidating potential mechanisms through which KBs modulate fibrotic pathways. A multifaceted interplay exists between KBs and key mediators of cardiac fibrosis. While some studies indicate a profibrotic role for KBs, others highlight their potential to attenuate fibrosis and cardiac remodeling. Mechanistically, KBs may regulate fibrotic pathways through modulation of cellular components such as cardiac fibroblasts, macrophages, and lymphocytes, as well as extracellular matrix proteins. Furthermore, the impact of KBs on cellular processes implicated in fibrosis, including oxidative stress, chemokine and cytokine expression, caspase activation, and inflammasome signaling is explored. While conflicting findings exist regarding the effects of KBs on these processes, emerging evidence suggests a predominantly beneficial role in mitigating inflammation and oxidative stress associated with fibrotic remodeling. Overall, this review underscores the importance of elucidating the complex interplay between KB metabolism and cardiac fibrosis. The insights gained have the potential to inform novel therapeutic strategies for managing cardiac fibrosis and associated cardiovascular disorders, highlighting the need for further research in this area.

Inhalation of ambient particulate matter (PM) and ozone (O 3 ) has been associated with increased cardiovascular morbidity and mortality. However, the interactive effects of PM and O 3 on cardiac dysfunction and disease have not been thoroughly examined, especially at a proteomic level. The purpose of this study was to identify and compare proteome changes in spontaneously hypertensive (SH) rats co-exposed to concentrated ambient particulates (CAPs) and O 3 , with a focus on investigating inflammatory and metabolic pathways, which are the two major ones implicated in the pathophysiology of cardiac dysfunction. For this, we measured and compared changes in expression status of 9 critical pro- and anti-inflammatory cytokines using multiplexed ELISA and 450 metabolic proteins involved in ATP production, oxidative phosphorylation, cytoskeletal organization, and stress response using two-dimensional electrophoresis (2-DE) and mass spectrometry (MS) in cardiac tissue of SH rats exposed to CAPs alone, O 3 alone, and CAPs + O 3 . Proteomic expression profiling revealed that CAPs alone, O 3 alone, and CAPs + O 3 differentially altered protein expression patterns, and utilized divergent mechanisms to affect inflammatory and metabolic pathways and responses. Ingenuity Pathway Analysis (IPA) of the proteomic data demonstrated that the metabolic protein network centered by gap junction alpha-1 protein (GJA 1) was interconnected with the inflammatory cytokine network centered by nuclear factor kappa beta (NF-kB) potentially suggesting inflammation-induced alterations in metabolic pathways, or vice versa, collectively contributing to the development of cardiac dysfunction in response to CAPs and O 3 exposure. These findings may enhance understanding of the pathophysiology of cardiac dysfunction induced by air pollution and provide testable hypotheses regarding mechanisms of action., Competing Interests: Declarations Conflict of interest The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Ethical Approval This manuscript has been reviewed by The Center for Computational Toxicology and Exposure, United States Environmental Protection Agency, and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the Agency nor does mention of trade names or commercial products constitute endorsement or recommendation for use., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Myocardial fibrosis is a typical pathological manifestation of hypertension. However, the exact role of sirtuin 7 (SIRT7) in myocardial remodeling remains largely unclear. Here, spontaneously hypertensive rats (SHRs) and angiotensin (Ang) II-induced hypertensive mice were pretreated with recombinant adeno-associated virus (rAAV)-SIRT7, copper chelator tetrathiomolybdate (TTM) or copper ionophore elesclomol, respectively. Compared with normotensive controls, reduced SIRT7 expression and augmented cuproptosis were observed in hearts of hypertensive rats and mice with decreased FDX1 levels and increased HSP70 levels. Notably, intervention with rAAV-SIRT7 and TTM strikingly prevented DLAT oligomers aggregation, and elevated ATP7A and TOM20 expressions, contributing to the alleviation of cuproptosis, mitochondrial injury, myocardial remodeling and heart dysfunction in spontaneously hypertensive rats and Ang II-induced hypertensive mice. In cultured rat primary cardiac fibroblasts (CFs), rhSIRT7 alleviated CuCl 2 , Ang II or elesclomol-induced cuproptosis and fibroblast activation by blunting DLAT oligomers accumulation and downregulating α-SMA expression. Additionally, conditioned medium from rhSIRT7-pretreated CFs remarkably mitigated cellular hypertrophy and mitochondrial impairments of neonatal rat cardiomyocytes, as well as cell migration and polarization of RAW 264.7 macrophages. Importantly, verteporfin reduced CuCl 2 -induced cuproptosis, mitochondrial injury and fibrotic activation in CFs. Knockdown of ATP7A with si-ATP7A blocked cellular protective effects of rhSIRT7 and verteporfin in CFs. In conclusion, SIRT7 attenuates cuproptosis, myocardial fibrosis and heart dysfunction in hypertension through the modulation of YAP/ATP7A signaling. Targeting SIRT7 is of vital importance for developing therapeutic strategies in hypertension and hypertensive heart disorders., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Erxian decoction (EXD) is an empirical formula for treating cardiovascular disease, our previous work has shown that EXD could improve the cardiovascular structure and function in ovariectomized (OVX) rats, but its pharmacological mechanism is still unclear., Materials and Methods: Network pharmacology was utilized to assess the key active components and central targets of EXD in treating postmenopausal cardiovascular disease. Then, an OVX rat model was established, HE staining and transmission electron microscope were utilized to observe myocardial tissue morphology, TUNEL staining was utilized to detect cardiomyocyte apoptosis, western blot, and ELISA were used to confirm efficacy and pathway of EXD., Results: The network pharmacology prediction results showed that 129 common targets were identified by intersecting EXD targets and postmenopausal cardiovascular disease targets, including AKT1, TNF, IL-6, IL-1β, PTGS2 and other core targets, apoptosis, PI3K/AKT, and other signaling pathways may be closely related to postmenopausal cardiovascular disease. After ovariectomy, the myocardial tissue of rats was damaged, the expression level of PI3K/AKT pathway-related molecules in the myocardial tissue were decreased, the apoptosis index of cardiomyocytes was increased, and the levels of inflammatory factors (TNF-α, IL-6, and IL-1β) were enhanced. EXD intervention could improve myocardial tissue injury, EXD could up-regulate the protein expression of PI3K and p-AKT in myocardial tissue, and thereby prevent myocardial cell apoptosis. At the same time, EXD downregulated the levels of inflammatory factors in serum of ovariectomized rats., Conclusion: EXD may prevent myocardial tissue damage through induction of the PI3K/AKT signaling pathway, thereby reducing cardiomyocyte apoptosis and inflammation. EXD may be a potential drug for the treatment of postmenopausal cardiovascular disease.

Myocardial infarction (MI) is a lethal cardiovascular disease worldwide. Emerging evidence has revealed the critical role of gut dysbiosis and impaired gut-brain axis in the pathological progression of MI. Tanshinone IIA (Tan IIA), a traditional Chinese medicine, has been demonstrated to exert therapeutic effects for MI. However, the effects of Tan IIA on gut-brain communication and its potential mechanisms post-MI are still unclear. In this study, we initially found that Tan IIA significantly reduced myocardial inflammation, apoptosis and fibrosis, therefore alleviating hypertrophy and improving cardiac function following MI, suggesting the cardioprotective effect of Tan IIA against MI. Additionally, we observed that Tan IIA improved the gut microbiota as evidenced by changing the α-diversity and β-diversity, and reduced histopathological impairments by decreasing inflammation and permeability in the intestinal tissues, indicating the substantial improvement of Tan IIA in gut function post-MI. Lastly, Tan IIA notably reduced lipopolysaccharides (LPS) level in serum, inflammation responses in paraventricular nucleus (PVN) and sympathetic hyperexcitability following MI, suggesting that restoration of Tan IIA on MI-induced brain alterations. Collectively, these results indicated that the cardioprotective effects of Tan IIA against MI might be associated with improvement in gut-brain axis, and LPS might be the critical factor linking gut and brain. Mechanically, Tan IIA-induced decreased intestinal damage reduced LPS release into serum, and reduced serum LPS contributes to decreased neuroinflammation with PVN and sympathetic inactivation, therefore protecting the myocardium against MI-induced injury., Competing Interests: Declarations Conflict of interest The authors declare that they have no known competing financial interest or personal relationships that could have appeared to influence the work reported in this paper. Ethical Approval All the animal experiments were approved by Xi’an Jiaotong University Laboratory Animal Administration Committee and were carried out strictly in accordance with Xi’an Jiaotong University Guidelines for Animal Experimentation. Consent to Participate Authors give full consent to participate. Consent for Publication Authors give full consent for publication., (© 2024. The Author(s).)

Myocardial fibrosis (MF) significantly compromises cardiovascular health by affecting cardiac function through excessive collagen deposition. This impairs myocardial contraction and relaxation and leads to severe complications and increased mortality. The present study employed network pharmacology and in vitro assays to investigate the bioactive compounds of Rhodiola rosea and their targets. Using databases such as HERB, the Encyclopedia of Traditional Chinese Medicine, Pubchem, OMIM and GeneCards, the present study identified effective components and MF‑related targets. Network analysis was conducted with Cytoscape to develop a Drug‑Ingredient‑Target‑Disease network and the STRING database was utilized to construct a protein‑protein interaction network. Key nodes were analyzed for pathway enrichment using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Molecular interactions were further explored through molecular docking techniques. The bioactivity of salidroside (SAL), the principal component of Rhodiola rosea , against MF was experimentally validated in H9c2 cardiomyocytes treated with angiotensin II and assessed for cell viability, protein expression and oxidative stress markers. Network pharmacology identified 25 active ingredients and 372 targets in Rhodiola rosea , linking SAL with pathways such as MAPK, EGFR, advanced glycosylation end products‑advanced glycosylation end products receptor and Forkhead box O. SAL showed significant interactions with core targets such as albumin, IL6, AKT serine/threonine kinase 1, MMP9 and caspase‑3. In vitro , SAL mitigated AngII‑induced increases in collagen I and alpha smooth muscle actin protein levels and oxidative stress markers, demonstrating dose‑dependent effectiveness in reversing MF. SAL from Rhodiola rosea exhibited potent anti‑oxidative properties that mitigated MF by modulating multiple molecular targets and signaling pathways. The present study underscored the therapeutic potential of SAL in treating oxidative stress‑related cardiovascular diseases.

Background: The T2* technique, used for quantifying myocardial iron content (MIC), has limitations in detecting early myocardial iron overload (MIO). The in vivo mapping of the myocardial T1 relaxation time is a promising alternative for the early detection and management of MIO., Methods: 32 β-thalassemia major (βTM) patients aged 11.5 ± 4 years and 32 healthy controls were recruited and underwent thorough clinical and laboratory assessments. The mid-level septal iron overload was measured through T1 mapping using a modified Look-Locker inversion recovery sequence with a 3 (3 s) 3 (3 s) 5 scheme. Septum was divided at the mentioned level into 3 zones corresponding to segments 8 and 9 in the cardiac segmentation model., Results: 21.9 % of βTM had clinical cardiac morbidity. The cut-off of T1 mapping of hepatic and myocardium to differentiate between the patients and control groups was ≤466 and ≥ 923 ms respectively. The T1 technique was able to detect 4 patients with high MIC, two of them were not detected by the T2* technique. There was a statistically significant correlation between the average T1 values of the studied zones in patients with βTM and the liver iron content (LIC), the T1 values within segment 8 of the liver, age of patients, the age at first transfusion, age of splenectomy and serum ferritin value., Conclusion: The addition of the T1 mapping sequence to the conventional T2* technique was able to increase the efficacy of the MIC detection protocol by earlier detection of MIO. This would guide chelation therapy to decrease myocardial morbidity., Competing Interests: Declaration of competing interest The authors declare no conflict of interest. They do not have a commercial or other association that might pose a conflict of interest (e.g., pharmaceutical stock ownership, consultancy, advisory board membership, relevant patents, or research funding)., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Progressive cardiac fibrosis, a hallmark of heart failure, remains poorly understood regarding Proprotein convertase subtilisin/kexin type 9 (PCSK9) 's role. This study aims to elucidate PCSK9's involvement in cardiac fibrosis. After ischemia/reperfusion (I/R) injury surgery in rats, PCSK9 inhibitors were used to examine their effects on the transforming growth factor-β1 (TGF-β1)/small mother against decapentaplegic 3 (Smad3) pathway and inflammation. Elevated PCSK9, TGF-β1, and Smad3 levels were observed in cardiac tissues post-I/R injury, indicating fibrosis. PCSK9 inhibition reduced pro-fibrotic protein expression, protecting the heart and mitigating I/R-induced damage and fibrosis. Additionally, it ameliorated cardiac inflammation and reduced post-myocardial infarction (MI) size, improving cardiac function and slowing heart failure progression. PCSK9 inhibitors significantly attenuate myocardial fibrosis induced by I/R via the TGF-β1/Smad3 pathway., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background and Aims: Hypertension is a potent risk factor for cardiovascular diseases, which are the leading worldwide cause of death. Within time increased blood pressure (BP) induces cardiac contractile dysfunction, metabolic alternations, and eventually, heart failure, which makes hypertension an area for seeking safe therapies such as phytocannabinoids., Methods and Results: In the present study spontaneously hypertensive rats (SHRs) were used as an experimental model of genetically induced hypertension, where cannabidiol (CBD) was applied as a potential treatment (intraperitoneally administered for 2 weeks, 10 mg/kg) for elevated BP and related metabolic disturbances. Langendorff working heart system, Western blotting as well as gas-liquid chromatography were applied to determine radiolabeled 3 H-palmitate uptake, incorporation, and oxidation, protein expression, as well as the content and fatty acid composition of different lipid fractions in the left ventricle and plasma, respectively. Most importantly, we noticed that 2-week CBD treatment was effective in upregulating ex vivo 3 H-palmitate uptake, oxidation, and its incorporation into triacylglycerol and cholesterol fractions with concomitant lowering free fatty acid, diacylglycerol, and phospholipid fractions, which was in agreement with in vivo studies and alternations in protein expressions of lipoprotein lipase, carnitine palmitoyltransferase I, 3-hydroxyacyl-CoA dehydrogenase, diacylglycerol acyltransferase 1, and adipose triglyceride lipase as well as proteins associated with eicosanoid signaling pathways and extracellular matrix remodeling in the heart of hypertensive rats., Conclusion: Our study reveals that 2-week CBD administration substantially affects the energetic substrate milieu in cardiac muscle regarding fatty acids uptake and their further utilization without parallel significant alternations in cardiovascular parameters., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.)

Arsenic trioxide (ATO) is a potent and highly effective chemotherapeutic agent for the treatment of acute promyelocytic leukemia. However, the clinical use of ATO is hampered by different cardiopathologic outcomes, such as arrhythmia and heart failure. Berberine has several beneficial effects because of its antioxidant activity; however, the potential cardioprotective function of this alkaloid against arsenic-induced cardiac toxicity has not been fully investigated. In this study, we evaluated the effect of ATO in rat heart tissue and the effect of berberine nanoparticles (NB) on cardiac enzyme levels, oxidative stress (OS) indices, and histopathological changes in heart tissue. Thirty Wistar rats were randomly allocated into five groups (n = 6): (1) Control animals that received 0.5 cc saline via gavage, (2) ATO group (4 mg/kg), (3) ATO + NB (2.5 mg/kg), (4) ATO + NB (5 mg/kg), and (5) ATO + NB (10 mg/kg) groups. Treatments were administered intraperitoneally for 45 days. Cardiac enzymes and OS biomarkers in heart tissue were measured. Histopathological examination of the heart tissue was also conducted at the end of the study. ATO injection significantly increased cardiac enzyme levels and OS biomarkers in rat's heart tissue. It also changed the histological features of the heart. NB administration significantly decreased the serum and tissue levels of cardiac enzyme and OS biomarkers in ATO-exposed animals (p < 0.05) and improved myocardial structural damage. NB, potent antioxidant, can reduce the unfavorable effects of ATO in rat heart tissue by balancing OS markers., Competing Interests: Declarations Conflict of interest The authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article. Ethical Approval This study was approved by the ethic committee of Birjand University of Medical Sciences, (number: IR.BUMS.REC.1401.070)., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Diabetic cardiomyopathy (DCM) is defined as cardiac dysfunction involving changes in structure, function, and metabolism in the absence of coronary artery disease, which eventually developed into heart failure. There is still a lack of effective drugs for the treatment of DCM, while the ameliorative effects of traditional herbs on DCM have been commonly reported. Polydatin (PD) is a glucoside derivative of traditional herbs of resveratrol, which has been shown to ameliorate the pathological development of DCM. However, the cardioprotective effect and mechanism of PD in the improvement of myocardial injury are still unclear., Aim of Study: This study aimed to investigate the cardio-protective role of PD on DCM and reveal the critical effect of Cav1 in PD' regulation of DCM., Materials and Methods: The Cav1 -/- and Cav1 +/+ mice and H9C2 cells were used to induce DCM models and then given PD treatment (150 mg/kg) or not. The cardiac functions of all mice were checked via echocardiography, and myocardial histological changes were measured by H&E, periodic acid-schiff (PAS) and Masson staining. The markers expression of heart fibrosis and inflammation, and hypertrophic factors were detected using western blotting. The NF-κB signaling activation was performed by confocal, immunohistochemical, Electrophoretic mobility shift assay (EMSA) and western blotting., Results: Here, we found that PD significantly improved the cardiac function and injury of diabetic Cav1 +/+ mice, and enhanced the expression of Cav1 in the cardiac tissues of diabetic Cav1 +/+ mice and HG-induced H9C2 cells. Further investigation showed that when Cav1 was knocked down, PD no longer plays the cardioprotective effect and inhibits the NF-κB signaling pathway activation in HFD/stz-treated diabetic mice and HG-induced H9C2 cells., Conclusion: These results demonstrated that PD inhibited the hyperglycemia-induced myocardial injury and inflammatory fibrosis of DCM models in vivo and in vitro, and targeting Cav1 may provide a novel understanding the mechanism of the treatment of PD in DCM., Competing Interests: Declaration of competing interest None., (Copyright © 2024. Published by Elsevier GmbH.)

Metabolic syndrome (MetS) is a condition that includes symptoms, such as obesity, hyperglycemia, and hypertension, which elevate cardiovascular risk. An impaired angiogenic response of endothelial cells (ECs) in heart and peripheral organs has been proposed in MetS, but the mechanisms of this phenomenon have not been thoroughly explored. Results obtained from evaluating the whole myocardium are inconsistent, since different types of cells react differently to MetS environment and a variety of molecular pathways are involved in the angiogenic response. Therefore, the aim of this paper was to study one selected pathway-the VEGF/VEGFR pathway, which regulates the angiogenic response and microvascular permeability in ECs isolated from db/db mouse hearts. The expression of mRNAs for VEGF/VEGFR axis proteins was assessed with RT-PCR in ECs isolated from control and db/db mouse myocardium. The density of CD31-, VEGFR2-, and VE-cadherin-positive cells was examined with confocal microscopy, and the ultrastructure of ECs was analyzed with transmission electron microscopy. The aortic ring assay was used to assess the capacity of ECs to respond to angiogenic stimuli. Our results showed a decreased number of microvessels, diminished expression of VE-cadherin and VEGFR2 and widened gaps between the ECs of microcapillaries. The aortic ring assay showed a diminished number of sprouts in db/db mice. These results may indicate that ECs in MetS enhance the production of mRNA for VEGF/VRGFR axis proteins, yet sprout formation and vascular barrier maintenance are limited. These novel data may provide a foundation for further studies on ECs dysfunction in MetS., (© 2024. The Author(s).)

Many foods including edible oils contain 2-monochloropropane-1,3-diol (2-MCPD), a processing-induced chemical contaminant. Cardiotoxic effects have been shown to result from oral 2-MCPD exposure in rodents, but the underlying mechanisms of action remain poorly understood. We undertook a comprehensive multi-omics approach to assess changes at the transcriptomic, proteomic, and oxylipin levels in heart tissues from male F344 rats that were exposed to 0 or 40 mg/kg BW/day of 2-MCPD in the diet for 90 days, in a regulatory compliant rodent bioassay. Heart tissues were collected for RNA sequencing, quantitative PCR analysis, proteomic analysis via two-dimensional gel electrophoresis and mass spectrometry, and targeted lipidomic profiling by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Transcriptomic and proteomic data analyses revealed upregulation of immune/inflammatory response processes and downregulation of energy metabolism and cardiac structure and functions. Among differentially expressed gene-protein pairs, coronin-1A, a key leukocyte-regulating protein, emerged as markedly up-regulated. Oxylipin profiling highlighted a selective suppression of docosahexaenoic acid-derived metabolites, suggesting a disruption in cardioprotective lipid pathways. These findings suggest that 2-MCPD disrupts homeostasis through inflammatory activation and suppression of metabolic and cardiac function. This research provides insights into 2-MCPD's cardiotoxicity, emphasizing the need for further studies to support hazard characterization., (© 2024. Crown.)

Background and Aims: Peroxisome proliferator-activated receptor α (PPARα) is crucial for regulating cardiac β-oxidation in the heart, liver, and kidney. Ageing can induce cardiac metabolic alterations, but the role of PPARα has not been extensively characterised. The aim of this research was to investigate the role of PPARα in the aged heart., Methods: Hyperpolarized [1- 13 C]pyruvate was used to evaluate in vivo cardiac carbohydrate metabolism in fed and fasted young (3 months) and old (20-22 months) PPARα knockout (KO) mice versus controls. Cine MRI assessed cardiac structural and functional changes. Cardiac tissue analysis included qRT-PCR and Western blotting for Pparα, medium chain acyl-CoA dehydrenase (MCAD), uncoupling protein (UCP) 3, glucose transporter (GLUT) 4 and PDH kinase (PDK) 1,2, and 4 expression., Results: PPARα-KO hearts from both young and old mice showed significantly reduced Pparα mRNA and a 58-59 % decrease in MCAD protein levels compared to controls. Cardiac PDH flux was similar in young control and PPARα-KO mice but 96 % higher in old PPARα-KO mice. Differences between genotypes were consistent in fed and fasted states, with reduced PDH flux when fasted. Increased PDH flux was accompanied by a 179 % rise in myocardial GLUT4 protein. No differences in PDK 1, 2, or 4 protein levels were observed between fed groups, indicating the increased PDH flux in aged PPARα-KO mice was not due to changes in PDH phosphorylation., Conclusions: Aged PPARα-KO mice demonstrated higher cardiac PDH flux compared to controls, facilitated by increased myocardial GLUT4 protein levels, leading to enhanced glucose uptake and glycolysis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The Pallas' spadefoot Pelobates vespertinus is a frog species native to eastern Europe and west Siberia. This species resists harsh winter conditions by moving up to 2 m underground. This amphibian is the first species known to withstand extreme air hypoxia. In this study, we investigated the metabolome of liver, heart, and brain of the Pallas' spadefoot after a month-long exposure of hypoxia, with oxygen levels reduced to approximately one-tenth of the air normal content. Surprisingly, our findings revealed a limited impact of hypoxia on the metabolomic profiles. Concentrations of glycolysis end products (lactate and alanine) increased only slightly compared to other amphibians under hypoxia, and no accumulation of succinate was observed. Furthermore, there were no notable changes in the content of adenosine phosphates. These results are consistent with a previous study, which indicated that the Pallas' spadefoot possesses relatively small glycogen and fat reserves before the winter compared to other frogs. It appears that this species conserves energy during winter by minimizing its metabolic activity. These findings corroborated the hypothesis that the survival of P. vespertinus under hypoxic conditions primarily relies on metabolic suppression rather than substantial energy reserves., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Studies have shown that Small conductance Ca2 + -activated K+ (SK) channel are expressed in fibroblasts. We aimed to determine the expression of SK2 channels in cardiac fibroblasts during myocardial hypertrophy and investigate its relationship with fibrotic remodeling. Myocardial hypertrophy and fibrotic remodeling induced by transverse aortic constriction (TAC) were assessed by echocardiography, Masson's trichrome staining and Western blot. Knockdown and overexpression of the SK2 protein were used to assess relationship between SK2 expression in fibroblasts and myocardial fibrosis. There is a positive correlation between myocardial fibrosis and SK2 channel protein expression during the development of myocardial hypertrophy. The differentiation and secretion of fibroblasts in mice with cardiac hypertrophy are enhanced, and the expression of SK2 channel protein is increased. Manipulating SK2 levels in fibroblasts can either promote or inhibit their differentiation and secretory function. Knocking down SK2 reduces the up-regulation of TGF β1, p-Smad2/3/GAPDH, p-p38/GAPDH, p-ERK1/2/GAPDH, and p-JNK/GAPDH proteins induced by Ang II in cardiac fibroblasts without significantly affecting total protein levels. AAV9-SK2-RNAi injection in mice improves cardiac function. Collectively, our study suggests that the expression of the SK2 channel is significantly increased in fibroblasts of mice with myocardial hypertrophy, potentially impacting myocardial fibrosis remodeling via the TGF-β signaling pathway., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Long-term dysfunction of glucose metabolism causes cardiac dysfunction called diabetic cardiomyopathy (DCM). To investigate the effect and underlying mechanism of RS on the process of DCM, mouse models induced by a high-fat diet (HFD) and streptozotocin (STZ) were fed RS (2 g/kg/day) and vehicle treatment (by oral gavage) for 14 weeks. Various analyses, including qRT-PCR, western blot, immunofluorescence staining, histology staining, cardiac function, and diversity detection of intestinal microbiota were performed. RS intervention could directly improve myocardial fibrosis, hypertrophy, apoptosis, and cardiac insufficiency in DCM. These beneficial effects may be achieved by elevating the expression of IGF-1, activating the ERK phosphorylation. Furthermore, by carrying out nano LC-MS/MS analyses and 16S rDNA sequencing, we found RS might primarily affect proteins in the cytoplasm involved in post-translational modification, protein conversion, and signal transduction mechanisms. RS altered intestinal microbiota and improved intestinal mucosal permeability towards a favorable direction in DCM. This multidimensional assessment of RS suggests that might be a promising approach towards the treatment of DCM., Competing Interests: Declarations of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background and Purpose: Adenosine receptor activation induces delayed, sustained cardioprotection against ischaemia-reperfusion (IR) injury (24-72 h), but the mechanisms underlying extended cardioprotection duration remain unresolved. We hypothesized that a positive feedback loop involving adenosine receptor-induced proteasomal degradation of adenosine kinase (ADK) and decreased myocardial adenosine metabolism extends the duration of cardioprotection., Experimental Approach: Mice were administered an ADK inhibitor, ABT-702, to induce endogenous adenosine signalling. Cardiac ADK protein and mRNA levels were analysed 24-120 h later. Theophylline or bortezomib was administered 24 h after ABT-702 to examine the late roles of adenosine receptors or proteasomal activity, respectively, in ADK expression and cardioprotection at 72 h. Coronary flow and IR tolerance were analysed by Langendorff technique. The potential for continuous adenosinergic cardioprotection was examined using heterozygous, cardiac-specific ADK KO (cADK +/- ) mice. Cardiac ADK expression was also examined after A 1 or A 3 receptor agonist, phenylephrine, lipopolysaccharide or sildenafil administration., Key Results: ABT-702 treatment decreased ADK protein content and provided cardioprotection from 24 to 72 h. ADK mRNA upregulation restored ADK protein after 96-120 h. Adenosine receptor or proteasome inhibition at 24 h reversed ABT-702-induced ADK protein deficit and cardioprotection at 72 h. cADK +/- hearts exhibited continuous cardioprotection. Diverse preconditioning agents also diminished cardiac ADK protein expression., Conclusion and Implications: A positive feedback loop driven by adenosine receptor-induced ADK degradation and renewed adenosine signalling extends the duration of cardioprotection by ABT-702 and possibly other preconditioning agents. The therapeutic potential of continuous adenosinergic cardioprotection is demonstrated in cADK +/- hearts., (© 2024 The Author(s). British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)

Mammalian cardiomyocytes become terminally-differentiated during the perinatal period. In rodents, cytokinesis ceases after a final division cycle immediately after birth. Nuclear division continues and most cardiomyocytes become binucleated by ∼11 days. Subsequent growth results from an increase in cardiomyocyte size. The mechanisms involved remain under investigation. Mitogen-activated protein kinases (MAPKs) regulate cell growth/death: extracellular signal-regulated kinases 1/2 (ERK1/2) promote proliferation, whilst c-Jun N-terminal kinases (JNKs) and p38-MAPKs respond to cellular stresses. We assessed their regulation in rat hearts during postnatal development (2, 7, 14, and 28 days, 12 weeks) during which time there was rapid, substantial downregulation of mitosis/cytokinesis genes (Cenpa/e/f, Aurkb, Anln, Cdca8, Orc6) with lesser downregulation of DNA replication genes (Orcs1-5, Mcms2-7). MAPK activation was assessed by immunoblotting for total and phosphorylated (activated) kinases. Total ERK1/2 was downregulated, but not JNKs or p38-MAPKs, whilst phosphorylation of all MAPKs increased relative to total protein albeit transiently for JNKs. These profiles differed from activation of Akt (also involved in cardiomyocyte growth). Dual-specificity phosphatases, upstream MAPK kinase kinases (MAP3Ks), and MAP3K kinases (MAP4Ks) identified in neonatal rat cardiomyocytes by RNASeq were differentially regulated during postnatal cardiac development. The MAP3Ks that we could assess by immunoblotting (RAF kinases and Map3k3) showed greater downregulation of the protein than mRNA. MAP3K2/MAP3K3/MAP4K5 were upregulated in human failing heart samples and may be part of the "foetal gene programme" of re-expressed genes in disease. Thus, MAPKs, along with kinases and phosphatases that regulate them, potentially play a significant role in postnatal remodelling of the heart., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Fibrosis is defined by the excessive accumulation of extracellular matrix (ECM) and constitutes a central pathophysiological process that underlies tissue dysfunction, across organs, in multiple chronic diseases and during aging. Myocardial fibrosis is a key contributor to dysfunction and failure in numerous diseases of the heart and is a strong predictor of poor clinical outcome and mortality. The excess structural and matricellular ECM proteins deposited by cardiac fibroblasts, is found between cardiomyocytes (interstitial fibrosis), in focal areas where cardiomyocytes have died (replacement fibrosis), and around vessels (perivascular fibrosis). Although myocardial fibrosis has important clinical prognostic value, access to cardiac tissue biopsies for histological evaluation is limited. Despite challenges with sensitivity and specificity, cardiac magnetic resonance imaging (CMR) is the most applicable diagnostic tool in the clinic, and the scientific community is currently actively searching for blood biomarkers reflecting myocardial fibrosis, to complement the imaging techniques. The lack of mechanistic insights into specific pro- and anti-fibrotic molecular pathways has hampered the development of effective treatments to prevent or reverse myocardial fibrosis. Development and implementation of anti-fibrotic therapies is expected to improve patient outcomes and is an urgent medical need. Here, we discuss the importance of the ECM in the heart, the central role of fibrosis in heart disease, and mechanistic pathways likely to impact clinical practice with regards to diagnostics of myocardial fibrosis, risk stratification of patients, and anti-fibrotic therapy., Competing Interests: Declaration of interest None., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study aimed to evaluate the effects of ursolic acid (UA) on Angiotensin II (Ang II)-treated neonatal rat cardiac fibroblasts (rCFs) as an in vitro model of cardiac fibrosis. The rCFs were isolated from two-day-old neonatal rats. An in vitro model of cardiac fibrosis was established using 500 nm Ang II treatment for 48 h. The cells were then treated with 5 and 10 μM of UA for 24 and 48 h. Masson's trichrome staining, hydroxyproline content assay, scratch assay, apoptosis assay, measurements of superoxide dismutase (SOD) and malondialdehyde (MDA) levels, real-time PCR, immunocytology and western blotting, were employed to assess the impact of UA. Ang II induced fibrosis in rCFs, as evidenced by the examination of various fibrotic markers. Upon treatment with 5 and 10 μM of UA, the amount of fibrosis in Ang II-treated rCFs was significantly decreased, so that the hydroxyproline concentration was reduced to 0.3 and 0.7 times, respectively. The RNA expression of the Col1a1, Col3a1, Tgfb1, Acta2 and Mmp2 genes had a decrease as well as Nrf2 and HO-1 had an increase after UA treatment. UA could lessen the harmful effects of cardiac fibrosis in a dose- and time-dependent manner, due to its antiapoptotic, antioxidant and cardioprotective properties. This suggests the potential of UA for treatment of cardiac fibrosis., Competing Interests: Declaration of competing interest The authors have no conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Myopathy leads to skeletal and cardiac muscle degeneration which is a major cause of physical disability and heart failure. Despite the therapeutic advancement the prevalence of particularly cardiac diseases is rising at an alarming rate and novel therapeutic targets are required. Nicotinamide riboside kinase-2 (NRK-2 or NMRK2) is a muscle-specific β1-integrin binding protein abundantly expressed in the skeletal muscle while only a trace amount is detected in the healthy cardiac muscle. The level in cardiac tissue is profoundly upregulated under pathogenic conditions such as ischemia and hypertension. NRK-2 was initially identified to regulate myoblast differentiation and to enhance the levels of NAD+, an important coenzyme that potentiates cellular energy production and stress resilience. Recent advancement has shown that NRK-2 critically regulates numerous cellular and molecular processes under pathogenic conditions to modulate the disease severity. Therefore, given its restricted expression in the cardiac and skeletal muscle, NRK-2 may serve as a unique therapeutic target. In this review, we provided a comprehensive overview of the diverse roles of NRK-2 played in different cardiac and muscular diseases and discussed the underlying molecular mechanisms in detail. Moreover, this review precisely examined how NRK-2 regulates metabolism in cardiac muscle, and how dysfunctional NRK-2 is associated with energetic deficit and impaired muscle function, manifesting various cardiac and skeletal muscle disease conditions., Competing Interests: Declaration of competing interest The authors declared no competing interest concerning this article's research, authorship, and/or publication., (Copyright © 2024 Elsevier B.V. All rights reserved.)

DNA methylation and microRNA (miRNA) expression are epigenetic mechanisms essential for regulating tissue-specific gene expression and metabolic processes. However, high-resolution transcriptome, methylome, or miRNAome data is only available for a few model organisms and selected tissues. Up to date, only a few studies have reported on gene expression, DNA methylation, or miRNA expression in adult equine tissues at the genome-wide level. In the present study, we used RNA-Seq, miRNA-seq, and reduced representation bisulfite sequencing (RRBS) data from the heart, lung, and liver tissues of healthy cold-blooded horses to identify differentially expressed genes (DEGs), differentially expressed miRNA (DE miRNA) and differentially methylated sites (DMSs) between three types of horse tissues. Additionally, based on integrative omics analysis, we described the observed interactions of epigenetic mechanisms with tissue-specific gene expression alterations. The obtained data allowed identification from 4067 to 6143 DMSs, 9733 to 11,263 mRNAs, and 155 to 185 microRNAs, differentially expressed between various tissues. We pointed out specific genes whose expression level displayed a negative correlation with the level of CpG methylation and miRNA expression and revealed biological processes that they enrich. Furthermore, we confirmed and validated the accuracy of the Next-Generation Sequencing (NGS) results with bisulfite sequencing PCR (BSP) and quantitative PCR (qPCR). This comprehensive analysis forms a strong foundation for exploring the epigenetic mechanisms involved in tissue differentiation, especially the growth and development of the equine heart, lungs, and liver., (© 2024. The Author(s).)

As the cornerstone of tissue engineering and regeneration medicine research, developing a cost-effective and bionic extracellular matrix (ECM) that can precisely modulate cellular behavior and form functional tissue remains challenging. An artificial ECM combining polysaccharides and fibrillar proteins to mimic the structure and composition of natural ECM provides a promising solution for cardiac tissue regeneration. In this study, we developed a bionic hydrogel scaffold by combining a quaternized β-chitin derivative (QC) and fibrin-matrigel (FM) in different ratios to mimic a natural ECM. We evaluated the stiffness of those composite hydrogels with different mixing ratios and their effects on the growth of human umbilical vein endothelial cells (HUVECs). The optimal hydrogels, QCFM1 hydrogels were further applied to load HUVECs into nude mice for in vivo angiogenesis. Besides, we encapsulated human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) into QCFM hydrogels and employed 3D bioprinting to achieve batch fabrication of human-engineered heart tissue (hEHT). Finally, the myocardial structure and electrophysiological function of hEHT were evaluated by immunofluorescence and optical mapping. Designed artificial ECM has a tunable modulus (220-1380 Pa), which determines the different cellular behavior of HUVECs when encapsulated in these. QCFM1 composite hydrogels with optimal stiffness (800 Pa) and porous architecture were finally identified, which could adapt for in vitro cell spreading and in vivo angiogenesis of HUVECs. Moreover, QCFM1 hydrogels were applied in 3D bioprinting successfully to achieve batch fabrication of both ring-shaped and patch-shaped hEHT. These QCFM1 hydrogels-based hEHTs possess organized sarcomeres and advanced function characteristics comparable to reported hEHTs. The chitin-derived hydrogels are first used for cardiac tissue engineering and achieve the batch fabrication of functionalized artificial myocardium. Specifically, these novel QCFM1 hydrogels provided a reliable and economical choice serving as ideal ECM for application in tissue engineering and regeneration medicine., (© 2024 Wiley Periodicals LLC.)

Aging is a risk factor for cardiovascular disease, the leading cause of death worldwide. Cardiac fibrosis is a harmful result of repeated myocardial infarction that increases risk of morbidity and future injury. Interestingly, both rates and outcomes of cardiac fibrosis differ between young and aged individuals, as well as men and women. Here, for the first time, we identify and isolate matrix-bound extracellular vesicles from the left ventricles (LVs) of young or aged males and females in both human and murine models. These LV vesicles (LVVs) show differences in morphology and content between these four cohorts in both humans and mice. LVV effects on fibrosis were also investigated in vitro, and aged male LVVs were pro-fibrotic while other LVVs were anti-fibrotic. From these LVVs, we could identify therapeutic miRNAs to promote anti-fibrotic effects. Four miRNAs were identified and together, but not individually, demonstrated significant cardioprotective effects when transfected. This suggests that miRNA synergy can regulate cell response, not just individual miRNAs, and also indicates that biological agent-associated therapeutic effects may be recapitulated using non-immunologically active agents. Furthermore, that chronic changes in LVV miRNA content may be a major factor in sex- and age-dependent differences in clinical outcomes of cardiac fibrosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objective: This paper was performed to decipher the serum microRNA (miR)-125b-5p expression in patients with dilated cardiomyopathy (DCM) combined with heart failure (HF) and its effect on myocardial fibrosis., Methods: Serum miR-125b-5p expression, LVEDD, LVESD, LVEF, LVFS, and NT-proBNP levels were evaluated in clinical samples. A rat DCM model was established by continuous intraperitoneal injection of adriamycin and treated with miR-125b-5p agomir and its negative control. Cardiac function, serum TNF-α, hs-CRP, and NT-proBNP levels, pathological changes in myocardial tissues, cardiomyocyte apoptosis, and the expression levels of miR-125b-5p and fibrosis-related factors were detected in rats., Results: In comparison to the control group, the case group had higher levels of LVEDD, LVESD, and NT-pro-BNP, and lower levels of LVEF, LVFS, and miR-125b-5p expression levels. Overexpression of miR-125b-5p effectively led to the improvement of cardiomyocyte hypertrophy and collagen arrangement disorder in DCM rats, the reduction of blue-stained collagen fibers in the interstitial myocardium, the reduction of the levels of TNF-α, hs-CRP, and NT-proBNP and the expression levels of TGF-1β, Collagen I, and α-SMA, and the reduction of the number of apoptosis in cardiomyocytes., Conclusion: Overexpression of miR-125b-5p is effective in ameliorating myocardial fibrosis.

Epicardial adipose tissue (EAT) is a fat depot covering the heart. No physical barrier separates EAT from the myocardium, so EAT can easily affect the underlying cardiac muscle. EAT can participate in the development and progression of heart failure with preserved (HFpEF) and reduced ejection fraction (HFrEF). In healthy humans, excess EAT is associated with impaired cardiac function and worse outcomes. In HFpEF, this trend continues: EAT amount is usually increased, and excess EAT correlates with worse function/outcomes. However, in HFrEF, the opposite is true: reduced EAT amount correlates with worse cardiac function/outcomes. Surprisingly, although EAT has beneficial effects on cardiac function, it aggravates ventricular arrhythmias. Here, we dissect these phenomena, trying to explain these paradoxical findings to find a target for novel heart failure therapies aimed at EAT rather than the myocardium itself. However, the success of this approach depends on a thorough understanding of interactions between EAT and the myocardium., (© 2024 World Obesity Federation.)

Cardiotoxicity is one of the side effects of the anti-cancer drug doxorubicin (DOX) that limits its clinical application. Betaine (BT) is a natural agent with promising useful effects against inflammation and oxidative stress (OS). We assessed the effects of BT on DOX-induced cardiotoxicity in mice. Forty-two male NMRI mice were assigned to six groups: I: control; II: BT (200 mg/kg; orally, alone); III: DOX (2.5 mg/kg; six injections (ip)) for two weeks; IV, V, VI: BT (50 mg/kg, 100 mg/kg, and 200 mg/kg; orally, once a day for two weeks, respectively) plus DOX administration. The cardiac enzymes like cardiac troponin-I (cTn-I), lactate dehydrogenase (LDH), and creatine kinase-MB (CK-MB) were assessed in serum. Oxidative/inflammatory markers like nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), reduced glutathione level (GSH), and glutathione peroxidase (GPx) activities were determined in cardiac tissue. The expressions of NOD-like receptor protein 3 (NLRP3), caspase-1, interleukin (IL)-1β, and silent information regulator 1 (SIRT1) proteins were also evaluated in cardiac tissue. The results indicated that DOX significantly increased LDH, CK-MB, cTn-I, MDA, and NO levels and also the caspase-1, NLRP3, and IL-1β expression. Furthermore, DOX caused a significant reduction in the GSH levels and SOD, CAT, GPX activities, and the expression of SIRT1 protein in heart tissue. However, BT significantly improved all studied parameters. The findings were confirmed by histopathological assessments of the heart. BT can protect against DOX-induced cardiotoxicity by suppressing the activation of NLRP3 and OS by stimulating the SIRT1 pathway., Competing Interests: Declarations. Ethical approval: This research was conducted according to the instructions of the Animal Ethics Committee of Ahvaz Jundishapur University of Medical Sciences for the use and care of laboratory animals (IR.AJUMS.ABHC.REC.1401.002). Consent to participate: Not applicable. Consent for publication: The authors confirm their consent for publication. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Myocardial fibroblasts transform into myofibroblasts during the progression of cardiac fibrosis, together with excessive cardiac fibroblast proliferation. Hence, the prevention and treatment of cardiac fibrosis are significant factors for inhibiting the development of heart failure. P-element Induced WImpy testis-interacting RNAs (PiRNA) are widely expressed in the heart, but their involvement in cardiac fibrosis has not yet been confirmed. We identified differentially expressed PiRNAs using Arraystar PiRNA expression profiling in Angiotensin II models of cardiac fibrosis in vivo and in vitro. We then explored cardiac-fibrosis-associated PiRNA-related proteins, RNA-protein interactomes, immunoprecipitation, and pulldown. We detected fibrosis markers and pathway-related proteins using immunofluorescence, qRT-PCR, and Western blot. We uncovered cardiac fibrosis associated PiRNA (CFAPIR) that was obviously dysregulated during cardiac fibrosis, whereas its overexpression reversed fibrosis in vivo and in vitro. Mechanistically, CFAPIR competitively bound muscleblind like protein 2 (MBNL2) and the cyclin-dependent kinase inhibitor P21 to regulate the TGF-β1/SMAD3 signaling pathway., Competing Interests: Declaration of competing interest The authors declare that there are no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The functioning of the cardiovascular system is critical for embryo survival. Cardiac contractions depend on the sequential activation of different classes of voltage-gated ion channels. Understanding the fundamental features of these interactions is important for identifying the mechanisms of pathologies development in the myocardium. However, at present there is no consensus on which ion channels are involved in the formation of automaticity in the early embryonic stages. The aim of this study was to elucidate the expression of genes encoding various types of ion channels that are involved in the generation of electrical activity chicken heart at different stages of ontogenesis. We analyzed the expression of 14 genes from different families of ion channels. It was revealed that the expression profiles of ion channel genes change depending on the stages of ontogenesis. The HCN4, CACNA1D, SCN1A, SCN5A, KCNA1 genes have maximum expression at the tubular heart stage. In adult, a switch occurs to the higher expression of CACNA1C, KCNH6, RYR and SLC8A1 genes. This data correlated with the results obtained by the microelectrode method. It can be assumed that the automaticity of the tubular heart is mainly due to the mechanism of the «membrane-clock» (hyperpolarization-activated current (I f ), Ca 2+ -current L-type (I CaL ), Na + -current (I Na ) and the slow component of the delayed rectifier K + -current (I Ks )). Whereas in adult birds, the mechanism for generating electrical impulses is determined by both « membrane- clock» and «Ca 2+ -clock»., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: This study aims to explore the correlation between PET and CMR in integrated [ 68 Ga]Ga-FAPI-04 PET/CMR multimodal imaging and its value in the diagnosis and risk assessment of hypertrophic cardiomyopathy (HCM)., Methods: This study included 20 HCM patients and 11 age- and gender-matched controls. PET analysis evaluated left ventricular (LV) [ 68 Ga]Ga-FAPI-04 uptake, including SUV max , TBR, cardiac fibroblast activity (CFA) and volume (CFV), and total SUV of the 16 segments. CMR tissue characterization parameters included cardiac function, myocardial thickness, late gadolinium enhancement (LGE), relaxation time, extracellular volume (ECV), and peak strain parameters. The 5-year sudden cardiac death (SCD) risk score and the 2-year and 5-year atrial fibrillation (AF) risk scores were calculated for each patient. The study analyzed differences between HCM patients and controls, the correlation between [ 68 Ga]Ga-FAPI-04 PET and concurrent CMR imaging results, and the predictive value of PET/CMR., Result: The FAPI uptake, myocardial mass, myocardial thickness, and T1/T2 mapping values were significantly higher in HCM patients compared to controls. Twenty HCM patients and their 320 myocardial segments were discussed. Increased [ 68 Ga]Ga-FAPI-04 uptake in the left ventricular wall was observed in 95% (19/20) of the patients, covering 48.8% (156/320) of the segments. On concurrent CMR, 80% (16/20) of the patients showed LGE, including 95 (29.7%) segments. The FAPI(+)LGE(+) segments exhibited the highest myocardial PET uptake, greatest thickness, longest T1/T2 native values, largest ECV value and the greatest loss of myocardial strain capacity (P < 0.05). There was a significant correlation between FAPI uptake and CMR parameters (P < 0.05). Higher [ 68 Ga]Ga-FAPI-04 uptake showed a positive correlation with SCD and AF risk scores (P < 0.05). The number of LGE(+) segments, mapping parameters, and ECV values in CMR also had prognostic significance. Combining PET with CMR aided in further risk stratification of HCM., Conclusion: [ 68 Ga]Ga-FAPI-04 PET/CMR multimodal imaging has potential value in the detection of damaged myocardial lesions and risk assessment of HCM patients. [ 68 Ga]Ga-FAPI-04 PET can detect more affected myocardium compared to CMR, and segments with abnormalities in both PET and CMR show more severe myocardial damage., Competing Interests: Declarations. Ethics approval: This study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the institutional review board of Shanghai East Hospital (Approval number: PW2024098). Consent to participate: Informed consent was obtained from the individual participant involved in the study. Consent to publish: Informed consent for publication was obtained from the individual participant for whom identifying information is included in this article. Competing interests: The authors declare that they have no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Excessive activation of cardiac fibroblasts (CFs) significantly contributes to adverse cardiac remodeling post-myocardial infarction (MI). CEMIP, initially recognized as an enzyme involved in hyaluronic acid (HA) degradation, has also been implicated in the activation of pulmonary fibroblasts. Nevertheless, the role and mechanism of CEMIP in adverse cardiac remodeling following MI remain largely unexplored., Materials and Methods: RNA sequencing (RNA-seq) was performed on cardiac tissue harvested from the infarct/peri-infarct region of mice 28 days post-MI. RNA-seq was conducted on primary cardiac fibroblasts (CFs) transfected with adenovirus overexpressing CEMIP. Adeno-associated virus serotype 9 (AAV9) was engineered for in vivo CEMIP knockdown to elucidate its impact on cardiac remodeling. Immunoprecipitation coupled with mass spectrometry (IP-MS) and co-immunoprecipitation (co-IP) were employed to elucidate the mechanism by which CEMIP affected cardiac remodeling., Key Findings: RNA-seq of fibrotic heart tissue at day 28 post-MI revealed a significant upregulation of CEMIP. In vitro, CEMIP facilitated the activation of cardiac fibroblasts. In vivo, knockdown of CEMIP markedly reduced cardiac fibrosis and improved cardiac function post-MI. IP-MS and co-immunoprecipitation (co-IP) confirmed that CEMIP interacted with TSP4 through the G8 domain. Further experiments confirmed that CEMIP promoted TSP4 degradation in lysosomes in an ACTN4-dependent manner, thereby activating the FAK signaling pathway., Significance: Our findings suggest that CEMIP significantly contributes to cardiac remodeling post-MI, which might be a novel approach for treating cardiac fibrosis following MI., Competing Interests: Declaration of competing interest The authors have no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Acute myocardial infarction, characterized by high morbidity and mortality, has now become a serious health hazard for human beings. Conventional surgical interventions to restore blood flow can rapidly relieve acute myocardial ischemia, but the ensuing myocardial ischemia-reperfusion injury (MI/RI) and subsequent heart failure have become medical challenges that researchers have been trying to overcome. The pathogenesis of MI/RI involves several mechanisms, including overproduction of reactive oxygen species, abnormal mitochondrial function, calcium overload, and other factors that induce cell death and inflammatory responses. These mechanisms have led to the exploration of antioxidant and inflammation-modulating therapies, as well as the development of myocardial protective factors and stem cell therapies. However, the short half-life, low bioavailability, and lack of targeting of these drugs that modulate these pathological mechanisms, combined with liver and spleen sequestration and continuous washout of blood flow from myocardial sites, severely compromise the expected efficacy of clinical drugs. To address these issues, employing conventional nanocarriers and integrating them with contemporary biomimetic nanocarriers, which rely on passive targeting and active targeting through precise modifications, can effectively prolong the duration of therapeutic agents within the body, enhance their bioavailability, and augment their retention at the injured myocardium. Consequently, these approaches significantly enhance therapeutic effectiveness while minimizing toxic side effects. This article reviews current drug delivery systems used for MI/RI, aiming to offer a fresh perspective on treating this disease.

Background: Currently, there is no effective therapy for takotsubo syndrome (stress-induced cardiac injury in humans) in the clinics. It has previously been shown that β 2 -adrenergic receptor (β 2 -AR) agonist formoterol reduces cardiomyocyte injury in experimental takotsubo syndrome., Objectives: The aim of this study was to investigate whether formoterol prevents apoptosis and necrosis of cardiomyocytes and endothelial cells in stress-induced cardiomyopathy., Methods: Stress-induced cardiac injury was induced by immobilization of rats for 2, 6, and 24 hours., Results: The myocardium of stressed rats showed a reduction in contractility and histological manifestations of cardiomyocyte damage: karyopyknosis, perinuclear edema of cardiomyocytes and endothelial cells, and microcirculation disturbances augmented with extended exposure to stress. In addition, apoptosis of endothelial cells was detected 6 hours after the onset of stress and peaked at 24 hours. Apoptosis of cardiomyocytes significantly gained only after 24 hours of stress exposure. These morphological alterations were associated with increased levels of serum creatine kinase-MB, syndecan-1, and thrombomodulin after 24 hours of stress. Administration of β 2 -AR agonist formoterol (50 μg/kg) four times during 24-hour stress exposure led to the improvement in myocardial inotropy, decrease in the severity of histological signatures, reduction in the number of TUNEL-positive cardiomyocytes, serum creatine kinase-MB, syndecan-1, and thrombomodulin levels., Conclusion: Present data suggest that apoptosis and necrosis of cardiomyocytes and necrosis of endothelial cells in stress-induced cardiac injury can be mitigated by activation of the β 2 -AR. However, formoterol did not eliminate completely cardiomyocyte apoptosis, histological alterations, or endothelium injury markers under stress., (© 2024 Société Française de Pharmacologie et de Thérapeutique. Published by John Wiley & Sons Ltd.)